1. Field of the Invention
The present invention relates to a weight scale with hybrid graduation. More particularly, the present invention relates to a weight scale having two or more graduations.
2. Description of Related Art
U.S. Pat. No. 6,246,017 discloses a portable scale comprising a housing with a slot and a graduation, a cap threadedly secured to a lower portion of the housing, a stem engaged through the cap and including a lower portion having a hook provided thereon for engaging with an object to be weighed, a head engaged on an upper portion of the stem that is slidably received in the housing, and a spring for biasing the head and the upper portion of the stem away from the cap.
An indicator is secured to the head that moves in concert with the stem for aligning with the graduation for indicating the weight of the object. A follower is slidably engaged in the slot of the housing and moved by the indicator when an object is placed on the hook for weighing purposes. The follower may stay at the position and will not be moved relative to the housing without any external force, such that the user may easily read the weight of the object even when the object has been removed from the portable scale.
When the indicator points at a position between two marks for the one unit of the portable scale, the user has to estimate the weight of the object with his or her eyes, leading to limitation in precision. Further, the portable scale has many elements and is thus too complicated, leading to an increase in the manufacturing cost and to inconvenient assembling procedures.